java - Java 电子邮件验证中的编译器错误

Question

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已关闭 10 年前。

我在 JAVA 中的电子邮件验证方面遇到问题(新手)，不断收到这些错误，并且对原因感到困惑。我应该收到此人的电子邮件，检查其设定标准(由我的教授)，然后获取有关测试的信息。当我检查电子邮件时，如果有错误，我应该显示错误。

错误

N:\Programming\Java\Homework\EmailAndGrade.java:29: illegal start of expression
    private static boolean validEmail(sEmail);
    ^
N:\Programming\Java\Homework\EmailAndGrade.java:29: illegal start of expression
    private static boolean validEmail(sEmail);
            ^
N:\Programming\Java\Homework\EmailAndGrade.java:29: ';' expected
    private static boolean validEmail(sEmail);
                  ^
3 errors

代码

public class EmailAndGrade
{

    public static void main(String[] args)
    {
        //Variables
        String sEmail, sError, sTest;
        int iTest;
        char cGrade;

        sEmail = JOptionPane.showInputDialog("Enter your email: ");


        private static boolean validEmail(sEmail);
                {
                // editing to make requirements listed
                // return email.matches("[A-Z0-9._%+-]+@[A-Z0-9.-]+\\.[A-Z]{2,4}");
                return email.matches("[A-Z0-9]{7}+@[springfieldcollege]+\\.[edu]");
                };

        sError = "One or More Errors with the Input Email.\n" +
                 "Email is Empty.\n" +
                 "Email must be less than 30 characters.\n" +
                 "Must end in: @springfieldcollege.edu.\n" +
                 "Can only have one @.\n" +
                 "Must start with A through Z or a through z.\n" +
                 "Can not have: # $ % & ,\n ";

        sTest = JOptionPane.showInptDialog("Enter Test Grade: ");

        iTest = Integer.parseInt(sTest);

        System.exit(0);


    }

    /*
        void checkEmails()
        {
            for(String email : emailAddresses) {
            if(validEmail(email)) {
                 // it's a good email - do something good with it

            }
            else {
                 // it's a bad email - do something... bad to it? sounds dirty...
                JOptionPane.showMessageDialog(null,
                                              sError,
                                              "Email Error - Killian O'Brien",
                                              JOptionPane.INFORMATION_MESSAGE);
                }
    }*/



}

*编辑

好的，现在我有了这段代码

package com.mkyong.regex;

import javax.swing.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class EmailAndGrade
{

public static void main(String[] args)
{
    //Variables
    String sEmail, sError, sTest;
    int iTest;
    char cGrade;

    sEmail = JOptionPane.showInputDialog("Enter your email: ");


    sError = "One or More Errors with the Input Email.\n" +
             "Email is Empty.\n" +
             "Email must be less than 30 characters.\n" +
             "Must end in: @springfieldcollege.edu.\n" +
             "Can only have one @.\n" +
             "Must start with A through Z or a through z.\n" +
             "Can not have: # $ % & ,\n ";

    sTest = JOptionPane.showInptDialog("Enter Test Grade: ");

    iTest = Integer.parseInt(sTest);

    System.exit(0);


}

public static boolean validEmail(String sEmail){
        return email.matches("[A-Z0-9]{7}+@[springfieldcollege]+\\.[edu]");
    }

public static void checkEmails(){
    for(String sEemail : emailAddresses) {
        if(validEmail(email)) {
            // it's a good email - do something good with it
        }
        else {
            // it's a bad email - do something... bad to it? sounds dirty...
            JOptionPane.showMessageDialog(null,
                                          sError,
                                          "Email Error - Killian O'Brien",
                                          JOptionPane.INFORMATION_MESSAGE);
                 }
             }
             }
}

我现在得到了这些

N:\Programming\Java\Homework\EmailAndGrade.java:37: cannot find symbol
symbol  : method showInptDialog(java.lang.String)
location: class javax.swing.JOptionPane
        sTest = JOptionPane.showInptDialog("Enter Test Grade: ");
                           ^
N:\Programming\Java\Homework\EmailAndGrade.java:47: cannot find symbol
symbol  : variable emailAddresses
location: class com.mkyong.regex.EmailAndGrade
        for(String email : emailAddresses) {
                           ^
N:\Programming\Java\Homework\EmailAndGrade.java:54: cannot find symbol
symbol  : variable sError
location: class com.mkyong.regex.EmailAndGrade
                                              sError,
                                              ^
N:\Programming\Java\Homework\EmailAndGrade.java:63: cannot find symbol
symbol  : variable email
location: class com.mkyong.regex.EmailAndGrade
        return email.matches("[A-Z0-9]{7}+@[springfieldcollege]+\\.[edu]");
               ^
4 errors

当我输入此内容时，我意识到我只是有一堆未声明的变量。这是正确的吗？

Answer 1

您正在另一个方法中实现方法validEmail main，这是不允许的。将下面的方法移出主函数(就在最后一行之前(在类右大括号}之前))。 此外，您还在方法实现中的两个位置(第一行结束和最后一行结束)使用了额外的分号。删除分号 ;。最后在方法签名中添加参数类型类(String)。更新后的方法应如下所示:

    private static boolean validEmail(String sEmail){
      // editing to make requirements listed
      // return email.matches("[A-Z0-9._%+-]+@[A-Z0-9.-]+\\.[A-Z]{2,4}");
      return email.matches("[A-Z0-9]{7}+@[springfieldcollege]+\\.[edu]");
    }